1. Field of the Invention
The present invention relates to a battery, and more particularly, to a secondary battery including a short-circuit plate installed on the bottom surface of a cap plate.
2. Description of the Related Art
A lithium ion secondary battery includes a positive electrode plate, a negative electrode plate, an electrolyte, and a separator, and repeats charge and discharge operations during use thereof.
In order to test the safety of a lithium ion secondary battery, many safety tests such as a penetration test, a compression test, and an oven test are carried out to eliminate the danger caused by damage to the lithium ion secondary battery during use thereof.
When a lithium ion secondary battery is compressed and damaged by an external impact, it loses its function as a battery and may ignite or explode. This is caused by a short circuit generated between a negative electrode collector and a positive electrode coating portion in the battery when the battery is compressed. Therefore, there have been many studies for eliminating the danger of ignition and explosion when a lithium ion secondary battery is compressed and damaged due to an external impact.